IGNITION SYSTEMS

Part One: Start Retard

20 degrees at 100 RPM, and decreases to 0 degrees at 500 RPM. This is a very useful feature which

eases the load on the starter motor when used with vehicles that have crank triggered ignition systems or

distributors with locked advances and 30 or more degrees of timing. However, there are applications

where the start retard is either not needed or not wanted. For example, motors with radical camshaft

profiles, large carbs and timing in the 15 to 25 degree BTDC range (Pro Mod motors, for example) may

experience lean-mixture backfiring during startup if the retard feature is active, especially if the tempera-

ture is colder than usual.

back of the ignition box. Cutting this loop eliminates the start retard. Earlier versions of the ignition don’t

have this feature, but the start retard can still be shut off. You must either send your ignition in to our service

department for modification, or, if you are attending an NHRA National event, you can bring your ignition to

our race support trailer and have it modified.

TECHNICAL BULLETIN

®

APRIL 26, 2000

Part Two: Function Selection

RPM limiters, timing retards, etc.). The instructions do not explain how to activate the functions.

Whether the user has a clutch pedal switch, a shifter button, or uses a timer, the auxiliary RPM limiters and the

timing retards need +12 volts to activate them.

CUT YELLOW WIRE LOOP TO

ELIMINATE START RETARD

AFTER CUTTING YELLOW WIRE,

USE SHRINK TUBING TO INSULATE

EXPOSED ENDS

Mallory-Ignition.com

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